fix: absolute path for sources and add sources in dependendency

package.json

@@ -43,7 +43,6 @@
   "dependencies": {
     "data-urls": "^2.0.0",
     "loader-utils": "^2.0.0",
-    "neo-async": "^2.6.1",
     "schema-utils": "^2.6.6",
     "source-map": "^0.6.0",
     "whatwg-encoding": "^1.0.5"

src/index.js

@@ -6,14 +6,13 @@ import fs from 'fs';
 import path from 'path';
 
 import validateOptions from 'schema-utils';
-import async from 'neo-async';
 import parseDataURL from 'data-urls';
+import { SourceMapConsumer } from 'source-map';
 import { labelToName, decode } from 'whatwg-encoding';
 import { getOptions, urlToRequest } from 'loader-utils';
 
-import flattenSourceMap from './utils/flatten';
-
 import schema from './options.json';
+import { flattenSourceMap, normalize, MapAgregator } from './utils';
 
 // Matches only the last occurrence of sourceMappingURL
 const baseRegex =
@@ -121,70 +120,68 @@ export default function loader(input, inputMap) {
       map = await flattenSourceMap(map);
     }
 
-    if (map.sourcesContent && map.sourcesContent.length >= map.sources.length) {
-      callback(null, input.replace(match[0], ''), map);
-
-      return;
-    }
-
-    const sourcePrefix = map.sourceRoot ? `${map.sourceRoot}${path.sep}` : '';
-
-    // eslint-disable-next-line no-param-reassign
-    map.sources = map.sources.map((s) => sourcePrefix + s);
-
-    // eslint-disable-next-line no-param-reassign
-    delete map.sourceRoot;
-
-    const missingSources = map.sourcesContent
-      ? map.sources.slice(map.sourcesContent.length)
-      : map.sources;
-
-    async.map(
-      missingSources,
-      // eslint-disable-next-line no-shadow
-      (source, callback) => {
-        resolve(context, urlToRequest(source, true), (resolveError, result) => {
-          if (resolveError) {
-            emitWarning(`Cannot find source file '${source}': ${resolveError}`);
+    const mapConsumer = await new SourceMapConsumer(map);
+
+    const resolvedSources = await Promise.all(
+      map.sources.map(async (source) => {
+        const fullPath = map.sourceRoot
+          ? `${map.sourceRoot}/${source}`
+          : source;
+        const sourceData = new MapAgregator({
+          mapConsumer,
+          source,
+          fullPath,
+          emitWarning,
+        });
 
-            callback(null, null);
+        if (path.isAbsolute(fullPath)) {
+          return sourceData.content;
+        }
+
+        return new Promise((promiseResolve) => {
+          resolve(
+            context,
+            urlToRequest(fullPath, true),
+            (resolveError, result) => {
+              if (resolveError) {
+                emitWarning(
+                  `Cannot find source file '${source}': ${resolveError}`
+                );
+
+                return promiseResolve(sourceData.placeholderContent);
+              }
+
+              sourceData.setFullPath(result);
+              return promiseResolve(sourceData.content);
+            }
+          );
+        });
+      })
+    );
 
-            return;
-          }
+    const resultMap = { ...map };
+    resultMap.sources = [];
+    resultMap.sourcesContent = [];
 
-          addDependency(result);
+    delete resultMap.sourceRoot;
 
-          fs.readFile(result, 'utf-8', (readFileError, content) => {
-            if (readFileError) {
-              emitWarning(
-                `Cannot open source file '${result}': ${readFileError}`
-              );
+    resolvedSources.forEach((res) => {
+      // eslint-disable-next-line no-param-reassign
+      resultMap.sources.push(normalize(res.source));
+      resultMap.sourcesContent.push(res.content);
 
-              callback(null, null);
+      if (res.source) {
+        addDependency(res.source);
+      }
+    });
 
-              return;
-            }
+    const sourcesContentIsEmpty =
+      resultMap.sourcesContent.filter((entry) => !!entry).length === 0;
 
-            callback(null, { source: result, content });
-          });
-        });
-      },
-      (err, info) => {
-        // eslint-disable-next-line no-param-reassign
-        map.sourcesContent = map.sourcesContent || [];
-
-        info.forEach((res) => {
-          if (res) {
-            // eslint-disable-next-line no-param-reassign
-            map.sources[map.sourcesContent.length] = res.source;
-            map.sourcesContent.push(res.content);
-          } else {
-            map.sourcesContent.push(null);
-          }
-        });
+    if (sourcesContentIsEmpty) {
+      delete resultMap.sourcesContent;
+    }
 
-        processMap(map, context, callback);
-      }
-    );
+    callback(null, input.replace(match[0], ''), resultMap);
   }
 }

src/utils.js

@@ -0,0 +1,90 @@
+import fs from 'fs';
+
+import sourceMap from 'source-map';
+
+async function flattenSourceMap(map) {
+  const consumer = await new sourceMap.SourceMapConsumer(map);
+  let generatedMap;
+
+  if (map.file) {
+    generatedMap = new sourceMap.SourceMapGenerator({
+      file: map.file,
+    });
+  } else {
+    generatedMap = new sourceMap.SourceMapGenerator();
+  }
+
+  consumer.sources.forEach((sourceFile) => {
+    const sourceContent = consumer.sourceContentFor(sourceFile, true);
+    generatedMap.setSourceContent(sourceFile, sourceContent);
+  });
+
+  consumer.eachMapping((mapping) => {
+    const { source } = consumer.originalPositionFor({
+      line: mapping.generatedLine,
+      column: mapping.generatedColumn,
+    });
+
+    const mappings = {
+      source,
+      original: {
+        line: mapping.originalLine,
+        column: mapping.originalColumn,
+      },
+      generated: {
+        line: mapping.generatedLine,
+        column: mapping.generatedColumn,
+      },
+    };
+
+    if (source) {
+      generatedMap.addMapping(mappings);
+    }
+  });
+
+  return generatedMap.toJSON();
+}
+
+function normalize(path) {
+  return path.replace(/\\/g, '/');
+}
+
+function readFile(fullPath, charset, emitWarning) {
+  return new Promise((resolve) => {
+    fs.readFile(fullPath, charset, (readFileError, content) => {
+      if (readFileError) {
+        emitWarning(`Cannot open source file '${fullPath}': ${readFileError}`);
+
+        resolve({ source: fullPath, content: null });
+      }
+
+      resolve({ source: fullPath, content });
+    });
+  });
+}
+
+class MapAgregator {
+  constructor({ mapConsumer, source, fullPath, emitWarning }) {
+    this.fullPath = fullPath;
+    this.sourceContent = mapConsumer.sourceContentFor(source, true);
+    this.emitWarning = emitWarning;
+  }
+
+  setFullPath(path) {
+    this.fullPath = path;
+  }
+
+  get content() {
+    return this.sourceContent
+      ? { source: this.fullPath, content: this.sourceContent }
+      : readFile(this.fullPath, 'utf-8', this.emitWarning);
+  }
+
+  get placeholderContent() {
+    return this.sourceContent
+      ? { source: this.fullPath, content: this.sourceContent }
+      : { source: this.fullPath, content: null };
+  }
+}
+
+export { flattenSourceMap, normalize, MapAgregator };

test/__snapshots__/loader.test.js.snap

@@ -50,7 +50,12 @@ Object {
 }
 `;
 
-exports[`source-map-loader should process external SourceMaps: warnings 1`] = `Array []`;
+exports[`source-map-loader should process external SourceMaps: warnings 1`] = `
+Array [
+  "ModuleWarning: Module Warning (from \`replaced original path\`):
+(Emitted value instead of an instance of Error) Cannot find source file 'external-source-map.txt': Error: Can't resolve './external-source-map.txt' in '/test/fixtures'",
+]
+`;
 
 exports[`source-map-loader should process inlined SourceMaps with charset: css 1`] = `
 "with SourceMap
@@ -64,7 +69,7 @@ Object {
   "file": "charset-inline-source-map.js",
   "mappings": "AAAA",
   "sources": Array [
-    "charset-inline-source-map.txt",
+    "/test/fixtures/charset-inline-source-map.txt - (normalized for test)",
   ],
   "sourcesContent": Array [
     "with SourceMap",
@@ -96,7 +101,12 @@ Object {
 }
 `;
 
-exports[`source-map-loader should process inlined SourceMaps: warnings 1`] = `Array []`;
+exports[`source-map-loader should process inlined SourceMaps: warnings 1`] = `
+Array [
+  "ModuleWarning: Module Warning (from \`replaced original path\`):
+(Emitted value instead of an instance of Error) Cannot find source file 'inline-source-map.txt': Error: Can't resolve './inline-source-map.txt' in '/test/fixtures'",
+]
+`;
 
 exports[`source-map-loader should skip invalid base64 SourceMap: css 1`] = `
 "without SourceMap
@@ -133,7 +143,7 @@ Object {
 exports[`source-map-loader should support absolute sourceRoot paths in sourcemaps: warnings 1`] = `Array []`;
 
 exports[`source-map-loader should support indexed sourcemaps: css 1`] = `
-"with SourceMap
+"console.log('with SourceMap')
 // Map taken from here
 // https://github.com/mozilla/source-map/blob/master/test/util.js - indexedTestMapDifferentSourceRoots
 "
@@ -147,7 +157,7 @@ Object {
   "mappings": "CAAC,IAAI,IAAM,SAAU,GAClB,OAAO,IAAI;CCDb,IAAI,IAAM,SAAU,GAClB,OAAO",
   "names": Array [],
   "sources": Array [
-    "/the/root/nested1.js",
+    "/test/fixtures/indexed-sourcemap/nested1.js - (normalized for test)",
     "/different/root/nested2.js",
   ],
   "sourcesContent": Array [
@@ -210,7 +220,12 @@ Object {
 }
 `;
 
-exports[`source-map-loader should use last SourceMap directive: warnings 1`] = `Array []`;
+exports[`source-map-loader should use last SourceMap directive: warnings 1`] = `
+Array [
+  "ModuleWarning: Module Warning (from \`replaced original path\`):
+(Emitted value instead of an instance of Error) Cannot find source file 'inline-source-map.txt': Error: Can't resolve './inline-source-map.txt' in '/test/fixtures'",
+]
+`;
 
 exports[`source-map-loader should warn on invalid SourceMap: css 1`] = `
 "with SourceMap
@@ -271,9 +286,6 @@ Object {
   "sources": Array [
     "missing-source-map2.txt",
   ],
-  "sourcesContent": Array [
-    null,
-  ],
   "version": 3,
 }
 `;

test/fixtures/charset-inline-source-map.txt

@@ -0,0 +1 @@
+// Content

test/fixtures/indexed-sourcemap/file.js

@@ -1,4 +1,4 @@
-with SourceMap
+console.log('with SourceMap')
 //#sourceMappingURL=file.js.map
 // Map taken from here
 // https://github.com/mozilla/source-map/blob/master/test/util.js - indexedTestMapDifferentSourceRoots